The present invention relates generally to electrically coupling systems and, more particularly, to an electrical system for coupling electrical power to a load mounted on a rotating shaft without mechanically contacting the shaft.
Inherent in the measurement of vibration, stress, torque and shaft horsepower associated with rotary shafts is the problem of introducing or coupling electrical power to the rotating shaft. In applications which will allow mechanical coupling or contact with the shaft, brush contacts are suitable. In applications where no mechanical coupling is allowed, rotary transformers have been used. However, prior art rotary transformers are relatively expensive and add size and weight to the rotating system. Typical prior art rotary transformers are disclosed in U.S. Pat. Nos. 2,531,288 (MacGeorge), 2,548,397 (Schaevitz), 3,850,030 (Adler) and 3,961,526 (Himmelstein).